The application of N-butyl Phosphorothioate Triamine and Dicyandiamide changes the soil N₂O production path

ABSTRACT

This study aims to explore the effect of nitrification inhibitor combined with urease inhibitor on soil N₂O emission under different nitrogen application depths. We carried out a soil column simulation test under 25°C. The combination of 1% N-butyl Phosphorothioate Triamine (NBPT) and 5% Dicyandiamide (DCD) was added to the soil. Anaerobically digested pig slurry (ADPS) was used as a nitrogen source and applied to four soil depths (soil surface (0 cm), 5 cm, 10 cm, and 15 cm, respectively). It was found that the inhibitory effects of NBPT and DCD on the soil N₂O emission were significantly affected by different nitrogen application depths. When the ADPS was applied at 15 cm, 10 cm, and on the soil surface, the combination of 1% NBPT and 5% DCD could inhibit soil N₂O emission by 46.1%, 21.7%, and 34.6%, respectively. Redundancy analysis (RDA) showed that the addition of inhibitors changed the microbial paths of soil N₂O production. The dominant microbial path of soil N₂O production after adding inhibitors was from ammonia oxidation dominated by AOB-amoA to denitrification dominated by nirS and nirK.

KEYWORDS:

• Depth
• inhibitor
• N₂O
• functional genes

Acknowledgement

Investigation and writing (original draft preparation), Q Y; methodology and writing (review and editing), J.F L; formal analysis, D Z; visualization, L.S Z; resources and supervision, K.Q Z; conceptualization and software, F W. All authors read and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/03650340.2022.2089354

Additional information

Funding

This work was supported by the National Key Research and Development Program of China [2017YFD0800403]; Yunnan Fundamental Research Projects [202101AT070002]; Central Public-interest Scientific Institution Basal Research Fund [Y2022PT06, Y2021XC18]; and Major Science and Technology Special Plan of Yunnan Province [202102AE090011].